Pseudo-Dynamic Active Earth Pressure on Battered Face Retaining Wall Supporting c-Φ Backfill Considering Curvilinear Rupture Surface

Introduction

The evaluation of seismic active earth pressure is very much essential for the design of retaining walls under seismic loading conditions. A number of research works have been done to predict the seismic active earth pressure on a rigid retaining wall. The pioneering works on retaining structures for granular backfill under seismic loading conditions are Okabe (1926) and Mononobe and Matsuo (1929) using a pseudo-static method. Sharma and Ghosh (2010) and Ghosh and Sengupta (2012) extended the pseudo-static method for c-Φ backfill to generate a single failure surface for the simultaneous action of unit weight, surcharge and cohesion. The influence of phase on the calculation of pseudo-static earth pressure on a retaining wall investigated by Steedman and Zeng (1990), Zeng and Steedman (1993). Choudhury and Nimbalkar (2005), Shekarian et al. (2008), Nimbalkar and Choudhury (2008), Ahmad and Choudhury (2008), Ghosh (2008) calculated the seismic pressure for different categories of retaining wall with cohesion-less backfill using pseudo-dynamic method. Later on, Ghosh and Sharma (2010) and Ghosh and Sharma (2012) extended this pseudo-dynamic method to solve the problems of a non-vertical retaining wall respectively considering the c-Φ nature of the backfill.

In most of the above studies, it is considered that the failure surface is linear planer surface. Babu and Basha (2008), Basha and Babu (2010) considered a logarithmic spiral surface for the analysis of retaining wall and abutment problems using a pseudo-dynamic method. Here in this analysis, an attempt is made to solve the problem considering non-linear failure surface which may or may not be always logarithmic spiral surface. The method of horizontal slices is used to solve this problem using pseudo-dynamic method. Depending upon the backfill and wall parameters, the failure surface at optimization may be sagging or hogging in nature.